Fault-tolerant virtual machine (VM) placement refers to the process of placing multiple copies of the same VM cloud application inside cloud data centers. The challenge is how to place required number of VM replicas while minimizing the number of physical machines (PMs) that store them, in order to save energy consumption of cloud data centers. We refer to it as fault-tolerant VM placement problem. In our previous work, we have proposed a greedy algorithm to solve this problem. In this paper, we compare it with an existing research that is based on well-known Welsh Powell Graph-Coloring Algorithm to place items into bins while considering the conflicts between items and items and items and bins. Via extensive simulations, we show that our greedy algorithm can turn off 40-50% more PMs than existing work and can place upto four times as many VM replicas as existing work, achieving much stronger fault-tolerance with less energy consumption. We also compare both algorithms with the optimal integer lin- ear programming (ILP)-based algorithm, which serves as the benchmark of the comparison.
IMG-DNA: Approximate DNA Storage for Images
Deoxyribonucleic Acid (DNA) as a storage medium with high density and long-term preservation properties can satisfy the requirement of archival storage for rapidly increased digital volume. The read and write processes of DNA storage are error-prone. Images
widely used in social media have the properties of fault tolerance which are well fitted to the DNA storage. However, prior work simply investigated the feasibility of DNA storage storing different types of data and simply store images in DNA storage, which did not fully investigate the fault-tolerant potential of images in the DNA storage. In this paper, we proposed a new image-based DNA system called IMG-DNA, which can efficiently store images in DNA
storage with improved DNA storage robustness. First, a new DNA architecture is proposed to fit JPEG-based images and improve the image’s robustness in DNA storage. Moreover, barriers inserted in DNA sequences efficiently prevent error propagation in images of DNA storage. The experimental results indicate that the proposed IMG-DNA achieves much higher fault-tolerant than prior work.
- Award ID(s):
- 1812537
- Publication Date:
- NSF-PAR ID:
- 10276611
- Journal Name:
- International Systems and Storage Conference (SYSTOR’21)
- Sponsoring Org:
- National Science Foundation
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